1. Field of the Invention
The present invention relates to a dishwasher and, more particularly, to a sump for collecting and/or storing washing fluid and pumping out the collected washing fluid with high pressure.
2. Description of the Related Art
Generally, a dishwasher is a machine that washes and dries dishes by spraying washing fluid or water with high pressure to upper and lower racks. The dishwasher includes a tub, a dish rack on which the dishes are arranged, a spray nozzle for spraying washing water to surfaces of the dishes, and a sump mounted on a bottom of the tub and collecting the washing water.
In the conventional dishwasher, a foreign object collection filter is mounted in the sump to collect the food wastes generated during the washing process. Alternatively, the foreign object is ground into fine particles so that they can be drained together with the used water during the draining process.
The sump includes a sump case for collecting the washing water, a sump cover covering the sump case, a filter for filtering the foreign objects, and a washing pump. These parts are held together by coupling members such as screws.
The conventional sump has the following problems:
The process for assembling the parts of the sump is complicated. That is, the parts constituting the sump are manufactured through individual processes and are subsequently held together by coupling members. As a result, the number of the coupling members increases and thus the manufacturing cost increases. In addition, there may be leak between the parts that are assembled.
The flow resistance increases during the supply of the washing fluid from the washing pump to the water guide connected to the upper and lower nozzles.
Since the washing pump and the foreign object collection space are provided as a single part, foreign objects may be introduced into the washing pump through a boundary between the foreign object collection space and the washing pumps and thus the foreign objects may be sprayed together with the washing water through the nozzles.
Since a vario valve for dividing and directing the washing water pumped by the washing pump to the lower nozzle and the water guide is mounted in the sump case, the pumped washing water may leak around the vario valve during the washing water dividing process, and thereby lower the water pressure.
The washing water may leak from the washing pump during the washing water pumping process.